Wireless services have become more and more popular. Such wireless services provide subscribers with mobility while still maintaining the ability to communicate either by voice or by data with others. As the number of wireless subscribers has increased, there has been a strain placed both on the communication networks themselves as well as the signaling networks which have been utilized for call setup, call control, and mobility management, such as the SS7 signaling network. As more sophisticated services have developed for the mobile subscriber, these services have grown to rely heavily upon available SS7 signaling network bandwidth. The combination of this increase of services and an increase in subscriber base threatens to place undue strain on the signaling system (SS7) network.
FIG. 1 illustrates a system in which the SS7 network is utilized for providing certain registration and services to a mobile subscriber. In this system a plurality of mobile switching centers (MSC) 10, 20, 30 are all coupled to a signaling transfer point (STP) 40 via the SS7 signaling network which is represented by the dashed lines. Each MSC has one or more base stations (BS), shown as elements 11, 12, 21, 22 and 31. The system also includes a service control point (SCP) and home location register (HLR), here shown as combined element 50. This element keeps track of information related to subscribers that are given wireless service. For example, as shown in the figure, the HLR maintains information about a number of mobile stations here shown as MS1, MS2, and MSx. The HLR keeps profile information in a database regarding various mobile subscribers. As an example, each profile can indicate information about the mobile identification number (MIN), the electronic serial number (ESN), information about where the mobile station is currently registered (that is, with which MSC the mobile station last registered), as well as a list of services for which the mobile subscriber has subscribed. Examples of services which may be available include: call waiting, caller ID, four-digit dialing, and other services which might be available to wireless users provided by various wireless service carriers.
Another element in the system is a Message Center (MC) 60. Such a Message Center, typically employed in wireless systems which provide a service known as Short Messaging Service (SMS) to subscribers, contains text messages which are to be provided to mobile stations. The messages typically are transported from MC 60 to the appropriate MSC via the SS7 network and are subsequently forwarded to the intended recipient mobile station MS.
Another element shown in the system is the Wireless Gateway Manager (WGM) 70 which can couple a plurality of wireless office systems (WOS) 71, 72 and 73 to the STP via, for example, a frame relay network 75. As is shown in the figure, at least one of the wireless office systems may include a voice mail system (VM) 76.
In the system of FIG. 1, presume that MSx 83 is one of the subscribers to the wireless service and has an affiliation with the voice mail system 76 and desires to receive a message waiting indicator (MWI) from that voice mail system even when away from the wireless office system 73. To accomplish that end in the prior art, the MSx registers with the MSC 10 via the base station 12 with which it is operating. MSC 10 then becomes the serving MSC (S-MSC) and sends a registration notification to SCP/HLR 50. This registration notification is transported via the SS7 network and through the signal transfer point 40. The SCP/HLR 50 in turn signals the VM 76 via the SS7 network, the STP 40, the WGM 70, the frame relay 75 and its associated WOS 73 so as to advise the VM as to where the MSx resides. If the VM has a message about which it desires to advise the MSx, then further signaling is transported via the SS7 network to the S-MSC 10 and a message waiting indication is sent out to the mobile station MSx 83. Alternatively, the HLR could have updated its own MWI information sometime prior to the registration by MSx and in such circumstance the HLR sends MWI information to the S-MSC. As can be seen, the signaling to provide this one service alone entails a not insignificant usage of the SS7 network. Other services, such as providing short messages from the message center via SS7 to the serving MSC, further burden the signaling network. Another service that consumes signaling network resources relates to voice messaging systems connected to MSCs whereby the SCP/HLR 50 updates its subscriber records concerning such messages and uses the signaling network to do so. Moreover, the very notion of carrying user data, rather than conventional signaling data such as call control, may itself be a burden on the signaling network. It would be beneficial if a technique could be provided for off-loading some of the subscriber services' demand from the SS7.